ABSTRACT

Intervertebral discs (IVDs) are the structures lying between the vertebral bodies, and which function is to transmit the mechanical loads exerted on the spine during motion to assure stable mobility. In postnatal organs/tissues, adult stem cells are fundamental to tissue homeostasis and injury repair when triggered with the appropriate signals. Adult stem cells have initially emerged as key elements of regenerative medicine therapies because of their differentiation potential properties into mature cells of different cell lineages. Due to the potential of adult stem cells to differentiate into chondrocytes, a cell type that shares common features with nucleus pulposus cells, they represent an attractive source of regenerative cells for IVD repair. The adult IVD is devoid of blood vessels and relies on both oxygen and nutrient supplies by diffusion from surrounding tissues, mainly through the end plates. One issue of debate into cell therapy for IVD degeneration pertains to the selection of the best tissue origin for adult stem cells.